Bicycle driving device

Abstract

A bicycle driving device including a shaft rotatably mounted on a part of a body frame; two crank arms perpendicularly disposed at both ends of the shaft so as to be symmetrical with each other at 180° with respect to a center of the shaft as a base point; a pedal attached to a tip of the crank arm; a gear mounted at one end of the shaft, which is provided with a chain; and balance weights disposed in a predetermined plane parallel to a surface formed by a rotary motion of the crank arm for generating kinetic energy equivalent to the kinetic energy generated by rotary motion of the crank arm and the pedal, wherein each mount position of those balance weights is set to be adjustable in an arc with a predetermined radius with respect to an axial center of the shaft.

1 . A bicycle driving device comprising:
 a shaft rotatably mounted on a part of a body frame;   two crank arms perpendicularly disposed at both ends of the shaft so as to be symmetrical with each other at 180° with respect to a center of the shaft as a base point;   a pedal attached to a tip of the crank arm;   a gear mounted at one end of the shaft, which is provided with a chain; and   balance weights disposed in a predetermined plane parallel to a surface formed by a rotary motion of the crank arm for generating kinetic energy equivalent to the kinetic energy generated by rotary motion of the crank arm and the pedal, wherein each mount position of those balance weights is set to be adjustable in an arc with a predetermined radius with respect to an axial center of the shaft.   
     
     
         2 . A bicycle driving device comprising:
 a shaft rotatably mounted on a part of a body frame;   two crank arms perpendicularly disposed at both ends of the shaft so as to be symmetrical with each other at 180° with respect to a center of the shaft as a base point;   a pedal attached to a tip of the crank arm;   a gear mounted at one end of the shaft, which is provided with a chain; and   a balance weight mounted on one surface of the gear for generating kinetic energy equivalent to the kinetic energy generated by rotary motion of the crank arm and the pedal on an extension of a longitudinal center line of the crank arm at one side, wherein a mount position of the balance weight is adjusted in an arc with a predetermined radius with respect to an axial center of the shaft.   
     
     
         3 . The bicycle driving device according to  claim 1 , wherein:
 the balance weight is of two-piece type having pieces symmetrical with each other with respect to the longitudinal center of the crank arm at one side; and   a mount position of each of the pieces on any one of surfaces of either the plane or the gear is adjustable in a circumferential direction.   
     
     
         4 . A bicycle driving device comprising:
 a shaft rotatably mounted on a part of a body frame;   two crank arms perpendicularly disposed at both ends of the shaft so as to be symmetrical with each other at 180° with respect to a center of the shaft as a base point;   a pedal attached to a tip of the crank arm;   a disk-like gear mounted at one end of the shaft, which is provided with a chain; and   a balance weight mounted on one surface of a disk-like member parallel to the gear on an extension of a longitudinal center line of any one of the crank arms so as to be slidably movable in a radiation direction of the disk-like member.   
     
     
         5 . A bicycle driving device comprising:
 a shaft rotatably mounted on a part of a body frame;   two crank arms perpendicularly disposed at both ends of the shaft so as to be symmetrical with each other at  180 ° with respect to a center of the shaft as a base point;   a pedal attached to a tip of the crank arm;   a gear mounted at one end of the shaft, which is provided with a chain;   a first balance weight mounted on a surface at one end of the shaft on an extension of a longitudinal center line of any one of the crank arms;   a fly wheel with a disk-like shape, mounted at the other end of the shaft; and   a second balance weight mounted on a surface of the fly wheel on an extension of a longitudinal center line of the other crank arm so as to have its mount position adjustable on a circumferential surface of the fly wheel in the circumferential direction.   
     
     
         6 . The bicycle driving device according to  claim 1 , wherein:
 the crank arm includes a first arm mounted at the crank shaft side, and a second arm mounted at the pedal side; and   a length between a center of the crank shaft and a center of a pedal mount part, which are defined by the arms is made adjustable.   
     
     
         7 . The bicycle driving device according to  claim 2 , wherein:
 the balance weight is of two-piece type having pieces symmetrical with each other with respect to the longitudinal center of the crank arm at one side; and   a mount position of each of the pieces on any one of surfaces of either the plane or the gear is adjustable in a circumferential direction.   
     
     
         8 . The bicycle driving device according to  claim 2 , wherein:
 the crank arm includes a first arm mounted at the crank shaft side, and a second arm mounted at the pedal side; and   a length between a center of the crank shaft and a center of a pedal mount part, which are defined by the arms is made adjustable.   
     
     
         9 . The bicycle driving device according to  claim 3 , wherein:
 the crank arm includes a first aim mounted at the crank shaft side, and a second arm mounted at the pedal side; and   a length between a center of the crank shaft and a center of a pedal mount part, which are defined by the arms is made adjustable.   
     
     
         10 . The bicycle driving device according to  claim 4 , wherein:
 the crank arm includes a first arm mounted at the crank shaft side, and a second arm mounted at the pedal side; and   a length between a center of the crank shaft and a center of a pedal mount part, which are defined by the arms is made adjustable.   
     
     
         11 . The bicycle driving device according to  claim 5 , wherein:
 the crank arm includes a first arm mounted at the crank shaft side, and a second arm mounted at the pedal side; and   a length between a center of the crank shaft and a center of a pedal mount part, which are defined by the arms is made adjustable.